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dressing up in fine clothes; splendid clothes; one's best clothes
パーティーのために盛装して出かけた。
I dressed up and went out for the party.
彼女は盛装した姿がとても美しかった。
She looked very beautiful dressed up.
結婚式には盛装で参列するのが礼儀だ。
It is proper etiquette to attend weddings in formal attire.